I am using Apple's original Lightning Digital AV-adapter (Lightning-to-HDMI dongle) to connect my iPhone to an external display via a HDMI cable.
I need to synchronize rendering with the external display's refresh rate, so I create a new CADisplayLink tied to the external display's UIScreen: UIScreen.screens[externalDisplayIdx].displayLink(withTarget:, selector:).
The callback is being called regularly, but with increasing delay relative to the CADisplayLink.timestamp, so the next time the callback is called, I have less and less time to draw the next frame (see the snippet below).
Assuming 60 FPS, the value of secondsTillDeadline starts at an arbitrary value in the range of approx -0.0001 to 0.0166667, and then it slowly decreases towards zero (and for a brief period it goes into small negative numbers). Once it reaches zero, it flips back to 0.0166667 and continues to decrease again. This cycle repeats indefinitely.
Changing the external display's resolution (UIScreen's mode) or the CADisplayLink's preferredFrameRateRange to a lower FPS does not seem to have any effect on the temporal drifting (even the rate of change seem to be the same).
When I create a new CADisplayLink for the iPhone's main screen, the value of secondsTillDeadline is stable, it does not drift and it is very close to 0.0166667, as expected.
Is this drift caused by the external monitor or by Apple's Lightning-to-HDMI dongle ...or is the problem somewhere else?
Can the drifting be stopped?
func onDisplayLinkUpdate(displayLink: CADisplayLink) {
// Gradually decreases from 0.01667 to -0.0001, then flips back to 0.01667 and continues to decrease
let secondsTillDeadline = displayLink.targetTimestamp - CACurrentMediaTime()
}
General
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I donate INPlayMediaIntent to systerm(donate success), but not show in control center
My code is as follows
let mediaItems = mediaItems.map { $0.inMediaItem }
let intent = if #available(iOS 13.0, *) {
INPlayMediaIntent(mediaItems: mediaItems,
mediaContainer: nil,
playShuffled: false,
playbackRepeatMode: .none,
resumePlayback: true,
playbackQueueLocation: .now,
playbackSpeed: nil,
mediaSearch: nil)
} else {
INPlayMediaIntent(mediaItems: mediaItems,
mediaContainer: nil,
playShuffled: false,
playbackRepeatMode: .none,
resumePlayback: true)
}
intent.suggestedInvocationPhrase = "播放音乐"
let interaction = INInteraction(intent: intent, response: nil)
interaction.donate { error in
if let error = error {
print("Intent 捐赠失败: \(error.localizedDescription)")
} else {
print("Intent 捐赠成功 ✅")
}
}
mac os 系统版本:26.0 (25A354)
Xcode版本:Version 26.0 (17A324)
项目编译报错
`SwiftExplicitDependencyCompileModuleFromInterface arm64 /Users/zhz/Library/Developer/Xcode/DerivedData/ModuleCache.noindex/AssetsLibrary-HTIJ05N58KN3.swiftmodule
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS26.0.sdk/usr/lib/swift/AssetsLibrary.swiftmodule/arm64e-apple-ios.swiftinterface:10:25: error: 'ALAssetsLibrary' is unavailable in iOS: Use PHPhotoLibrary from the Photos framework instead
8 | public import _StringProcessing
9 | public import _SwiftConcurrencyShims
10 | extension AssetsLibrary.ALAssetsLibrary {
| `- error: 'ALAssetsLibrary' is unavailable in iOS: Use PHPhotoLibrary from the Photos framework instead
11 | #if compiler(>=5.3) && $NonescapableTypes
12 | @available(iOS, introduced: 9.0, deprecated: 9.0, obsoleted: 26.0)
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS26.0.sdk/System/Library/Frameworks/AssetsLibrary.framework/Headers/ALAssetsLibrary.h:80:12: note: 'ALAssetsLibrary' was obsoleted in iOS 26.0
78 |
79 | OS_EXPORT AL_DEPRECATED(4, "Use PHPhotoLibrary from the Photos framework instead")
80 | @interface ALAssetsLibrary : NSObject {
| `- note: 'ALAssetsLibrary' was obsoleted in iOS 26.0
81 | @package
82 | id _internal;
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS26.0.sdk/usr/lib/swift/AssetsLibrary.swiftmodule/arm64e-apple-ios.swiftinterface:1:1: error: failed to build module 'AssetsLibrary'; this SDK is not supported by the compiler (the SDK is built with 'Apple Swift version 6.2 effective-5.10 (swiftlang-6.2.0.17.14 clang-1700.3.17.1)', while this compiler is 'Apple Swift version 6.2 effective-5.10 (swiftlang-6.2.0.19.9 clang-1700.3.19.1)'). Please select a toolchain which matches the SDK.
Hello,
I'm working on a Flutter app targeting both Android and iOS, where I implemented ShazamKit.
In order to achieve that, I first tried with the flutter_shazam_kit package, but since it's not maintained anymore, I forked it here, and tried to update it to meet the Google Play Store requirements, as you can see here:
https://github.com/mregnauld/flutter_shazam_kit/tree/fix-16k
Unfortunately, after trying everything, my app still doesn't meet the (not so) new 16 KB native library alignment. Also, I'm 100% sure it comes from that because the error message disappears if I remove that package from my app.
So after investigating, it seems that the problem comes from the ShazamKit for Android (that you can find here: https://developer.apple.com/download/all/?q=Android%20ShazamKit), and especially the .so files in the .aar file.
Is there anything I can do to fix that, or should I wait before the ShazamKit team fix that?
I'm totally stuck with that so any help is highly appreciated.
Thanks.
I use
htttps://api.music.apple.com/v1/me/library/playlists/${playlistId}/tracks
to add tracks to a playlist I created.
How do I DELETE tracks from the playlist?
The documentation does not mention a method for this. I have tried calling DELETE methods in various combinations but nothing seems to work.
Is this possible?
Dear Apple Developer Team,
On iOS 26, the contents of PDF pages appear to be swapped.
Could you please advise if there is a workaround or a planned fix for this issue?
Steps to Reproduce:
Download the attached PDF on iOS 26.
Open the PDF in the Files app.
Tap the PDF to view it in Quick Look.
Navigate to page 5.
Expected Result:
The page number displayed at the bottom should be 5.
Actual Result:
The page number displayed at the bottom is 4.
Issue:
This is not limited to page 5—multiple page contents appear to be swapped.
I have also submitted feedback via Feedback Assistant (FB20743531) on October 20.
Best regards,
Yoshihito Suezawa
Has anyone been able to successfully use MusicCatalogSearchRequest in a playgrounds app?
I have configured my playground similar to a regular app: app id with automatic music token generation turned on, music access authorized within the app itself, but whenever I query MusicCatalogSearchRequest I get an error thrown with .developerTokenRequestFailed.
Considering musickit is restricted in the sim, it would not surprise me if it was the same in playgrounds but it would be super helpful if I could prototype with musickit in playgrounds 4!
Add RPSystemBroadcastPickerView to the app,
After clicking, no method of SampleHandler is triggered
I often find when doing basic actions in MusicKit it is incredibly slow compared to Apple's Music App. I've tried different versions, devices, networks, Apple's sample code, it all throughout the last several years, and it is all the same. Does anyone else have this issue?
In SwiftUI there is a built-in component for displaying album artworks called Artwork but there is no equivalent for UIKit.
My current approach is to use the .url() method to read image's URL and download the image or read it from the disk but the performance is much worse than it was previously with MPMediaItem's artworkImage method.
let artworkQueue = DispatchQueue(
label: "MusicKit-ArtworkQueue",
qos: .default,
attributes: .concurrent
)
let artworkSemaphore = DispatchSemaphore(value: 5)
extension Song {
func artworkImage(for size: CGSize, completion: @escaping (UIImage?) -> Void) {
artworkQueue.async {
artworkSemaphore.wait()
defer {
artworkSemaphore.signal()
}
let imageURL = artwork?.url(
width: Int(size.width),
height: Int(size.height)
)
// I hate doing this as it might very well break in the future
guard let imageURL, imageURL.scheme == "musicKit"
else {
return completion(nil)
}
guard let imageData = try? Data(contentsOf: imageURL),
let image = UIImage(data: imageData) else {
return completion(nil)
}
completion(image)
}
}
}
I really dislike this approach because it feels hacky but somewhat works. You might ask what's the semaphore for? Well, without it I could notice that MusicKit was choking and after reading too many artworks at once.
Can someone from Apple please provide us with an example on how to use MusicKit with UIKit properly?
Ideally (IMO) we would have a method defined on Song and other MusicKit structures that returns the image for us, just like MPMediaItem had the .artwork() method. It would make our lives so much easier.
Hi,
just generated a HDR10 MVHEVC file, mediainfo is below:
Color range : Limited
Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Codec configuration box : hvcC+lhvC
then generate the segment files with below command:
mediafilesegmenter --iso-fragmented -t 4 -f av_1 av_new_1.mov
then upload the segment files and prog_index.m3u8 to web server.
just find that can not play the HLS stream on Safari...
the url is http://ip/vod/prog_index.m3u8
just checked that if i remove the tag Transfer characteristics : PQ when generating the MVHEVC file.
above same mediafilesegmenter command and upload the files to web server.
the new version of HLS stream is can play on Safari...
Is there any way to play HLS PQ video on Safari. thanks.
Hi All,
I am working on a DJ playout app (MACOS). The app has a few AVAudioPlayerNode's combined with the ApplicationMusicPlayer from Musickit. I can route the output of the AVaudioPlayer to a hardware device so that the audio files are directed to their own dedicated output on my Mac. The ApplicationMusicPlayer is following the default output and this is pretty annoying.
Has anyone found a solution to chain the ApplicationMusicPlayer and get it set to a output device?
Thanks
Pancras
Hello,
I'm sporadically getting the unknown CoreHaptics error described in the title, when trying to create a CHHapticPatternPlayer from an .ahap file — this does not occur in a repeatable manner, unfortunately...
This occurs in a SpriteKit game, running on both iOS 17 and 18.
Anyone know what the error means, since it's apparently undocumented?
Note that the haptics engine is started right before creating the pattern, and the start request doesn't appear to fail...
Thanks,
D.
Will the restrictions on callkit be lifted in China in 2025? If so, how can you legally use callkit in China?
In the past, when using Lightning, many external devices had to go through MFi certification. However, since the iPhone 15 switched from Lightning to USB-C, is MFi certification still required?
Our company has developed several UVC devices, and we have confirmed that iPads can read frames from external cameras through the external device type in AVFoundation. However, this is not supported on iPhones.
We are currently exploring feasible ways to enable UVC device support on iPhones. Is MFi certification the only option? If so, is the MFi certification process for USB-C the same as it was for Lightning? Does it still require purchasing an MFi chip and manufacturing specially designed USB-C cables?
I've established proper authorization for general music api calls, but when I use that same authorization to retrieve metadata for the latest music feeds (see https://developer.apple.com/documentation/applemusicfeed/requesting-a-feed-export), I get a 401 Unauthorized error.
As per the documentation, I'm simply issuing a GET against https://api.media.apple.com/v1/feed/album/latest.
Are there different entitlements needed for the Music Feed API?
Topic:
Media Technologies
SubTopic:
General
On an iPhone running iOS 26 beta 5, url(for: FilePath("subdir/asset.mov")) most always throws this error:
The URL for “subdir/asset.mov” couldn’t be retrieved: “asset.mov” couldn’t be copied to “subdir” because an item with the same name already exists.
Yet, contents(at: FilePath("subdir/asset.mov")) always returns Data for a playable AVMovie.
How can I avoid this url(for:) error?
The asset pack in question is downloaded. The error persists even after pack deletion, redownload, relaunch, and combinations of that.
// Assets repo root
subdir.aar
subdir/asset.mov
subdir/asset_thumb.heic
subdir/Manifest.json
// Manifest.json
{
"assetPackID": "subdir",
"downloadPolicy": {
"onDemand": {}
},
"fileSelectors": [
{
"directory": "subdir",
},
],
"platforms": [
"iOS",
"visionOS"
]
}
xcrun ba-package subdir/Manifest.json -o subdir.aar
xcrun ba-serve --host 192.168.0.10 -p 443 subdir.aar
I'm wondering if someone happened issues with currentPlaybackRate in released version of iOS 26.0?
There is no issue happened in case of iOS 18.5.
When I changed currentPlaybackRate on iOS 26.0, it seems to unexpectedly change currentPlaybackRate to be 0 or 1.0 forcibly no matter DRM or non-DRM contents. And also, playing music will be abnormal behavior and unstable with noise if currentPlaybackRate is not 1.0. And changes stop state and play state frequently.
Hello,
I'm new to the Swift MusicKit API and am starting with the implementation in iOS 16.
I'm getting stuck on an issue where there is no background or text color associated with the Artwork object. Is this something you have to make an additional property request for, and if so, how do you do that?
var catalogSearch = MusicCatalogResourceRequest<Album>(matching: \.id, equalTo: item.id)
let catalogResponse = try await request.response()
guard let firstItem = catalogResponse.items.first else {
return
}
In this example, firstItem.artwork only contains the url and what look like incorrect max width/height values.
here's a printout of firstItem.artwork
Optional(Artwork(
urlFormat: "musicKit://artwork/library/5F37858D-F46B-4F12-BA67-40FA8DD63D87/{w}x{h}?at=item&fat=&id=7718670444435992305&lid=5F37858D-F46B-4F12-BA67-40FA8DD63D87&mt=music&aat=Music122/v4/37/25/f5/3725f515-249f-7b91-77bb-f479cd48201c/22UMGIM32254.rgb.jpg",
maximumWidth: 0,
maximumHeight: 0
))
The two ScreenCaptureKit WWDC22 sessions show how to capture with the new framework but the retina factor is hardcoded to 2 in SCStreamConfiguration.
When using on a non-retina display, the screencapture is floating on the upper-left corner of the image buffer.
There does not seem to be a simple way to retrieve the retina factor from the SCShareableContent data (when configuring the capture).
When processing the streaming output, the SCStreamFrameInfo attachment is supposed to have a scaleFactor property but .scaleFactor does not return a value.
I have found out that the attachement dictionary contains SCStreamUpdateFrameDisplayResolution. This entry gives me the retina factor but it is not an official SCStreamFrameInfo key. I list the keys to access it.
What is the proper way with ScreenCapture to handle the retina factors ?